Freedom Partners, a political group allied with billionaire brothers Charles and David Koch, has booked millions of dollars of new air time in New Hampshire and five other states with competitive Senate races according to recent ad documents.

The biggest reservation is at an ABC-affiliate in New Hampshire where viewers would see roughly 95 ad spots a week from the start of September through Election Day. The total cost of running ads at that one station alone will come to more than $1.2 million–assuming they aren’t canceled.

The other ad bookings are slated to run in Iowa, Colorado, North Carolina, Arkansas and Michigan. The run dates vary; most of the ads would start in August and run for about a month, though spots in Iowa would run from September through the election.

It’s unclear what tack the spots will take, though a document in Colorado Springs says the ads will highlight Colorado Sen. Mark Udall’s support for the Affordable Care Act. A previous round of ads that aired in April hit Democratic senators and candidates on a similar subject in Iowa, Colorado, Alaska, Louisiana and Michigan.

Although TV stations are required to name the candidates targeted by political ads, Manchester, N.H.-based WMUR instead just listed “TBD” on disclosure forms. Station Manager Jeff Bartlett said station personnel asked about the ads, but hadn’t been told who they would support. New Hampshire’s primary isn’t until Sept. 9, he added.

So far this year, Freedom Partners’ ads have focused on Senate races, but in addition to Sen. Jeanne Shaheen’s competitive reelection bid, New Hampshire is also the scene of two closely fought House contests: The state’s First Congressional District, held by Democrat Carol Shea-Porter, is a tossup, according to the Rothenberg Political Report. But the state’s Second Congressional District, held by Ann McLane Kuster, also a Democrat, could be close too; Rothenberg considers it “lean Democrat”.

David and Charles Koch and their network of like-minded conservative donors hope to spend $290 million electing Republicans, according to the Daily Beast. Freedom Partners is the name of two political groups: a nonprofit business league that funneled $230 million to other political nonprofits in 2012 as well as a super PAC that formed in June. The super PAC reports its spending and fundraising to the Federal Election Commission, while the nonprofit arm does not. Other dark money Koch affiliates have already run TV ads this cycle including Americans For Prosperity, American Future Fund, American Energy Alliance, Libre Initiative — which targets Hispanics, Generation Opportunity — which targets younger voters and the 60-plus Association–which targets older voters.

Freedom Partners–the nonprofit business league–remained in the shadows until tax returns showing the group’s grantmaking were due last year. Then Freedom Partners, whose full name is Freedom Partners Chamber of Commerce, outed itself, saying that it had transformed into a think tank. At the time representatives said the group had 200 “members” paying at least $100,000 apiece, including one who gave $25 million. It’s unclear from the TV ad station filings whether the nonprofit or the super PAC is paying for the ads. [More than 100 of the raw documents relating to the group’s newest ad buy are available on Sunlight’s Political Ad Sleuth ].

While some dark money groups tout their spending in press releases as part of an effort to receive free media coverage, Freedom Partners’ media strategy has been lower-profile. For the April ad buys, the group didn’t put out a press release until after they had been written about elsewhere. The current round of buys doesn’t appear on the groups’ YouTube page and the site’s last news release is months old. A spokesman didn’t immediately return a call for comment.